1. Field of the Disclosure
The disclosure relates to structures and formation methods of memory devices, and in particular to structures and formation methods of resistive random-access memory (RRAM) devices.
2. Description of the Related Art
Recently, a variety of consumer electronic products have become popular, increasing the demand for non-volatile memory devices. Flash memory is one of the mainstream non-volatile memory devices. However, since the size of the devices continues to shrink, flash memory devices have encountered issues such as high operation voltages, slow operation speeds, and bad data retention ability. As a result, future development of the flash memory device is limited.
Therefore, many materials and apparatuses of new type non-volatile memory devices are under development. New type non-volatile memory devices include, for example, magnetic random access memory (MRAM) devices, phase change memory (PCM) devices, and resistive random access memory (RRAM) devices. Among the non-volatile memory devices, RRAM devices have many advantages such as low power consumption, low operation voltages, short write and erase times, high reliability, long memory time, non-destructive read-out, multi-state memory, process simplicity, and only a small area is required.
However, the yield and the efficiency of RRAM devices still need further improvement.